GL 308 and GL 309

Overview

The GL 308 and GL 309 are GE Vernova live tank circuit breakers for outdoor installation provided with third-generation self-blast interrupter chambers and spring-operated mechanisms that operate on an energy-optimized self-blast principle. The breakers are preset and completely pre-assembled at the factory, with pole units pre-filled with SF₆ and an interrupter chamber that can be independently disassembled without removing the entire pole column. Protective and quality features include a pressure relief system, a temperature-compensated density monitor with two-stage transducer and three-color dial, an easy-access SF₆ filling connection (type DILO), an SF₆ non-return (check) valve on each pole column, protected opening springs inside each pole column, hot-dip galvanized steel parts, an aluminum mechanism housing, and a spring-operated mechanism with an externally visible position indicator. The product family meets national and international standards via comprehensive type tests according to the latest IEC and ANSI standards and is developed and produced in compliance with ISO 9001, ISO 14001 and OHSAS 18001 quality standards. GL 308 F1/3120 and GL 308 F3/3120 (52 kV, 50 Hz) — rated voltage: 52 kV; rated frequency: 50 Hz; rated normal current: up to 2,000 A; rated short-circuit breaking current: up to 31.5 kA; rated short-circuit making current: 80 kA; rated duration of short-circuit: 3 s; opening time: 38 ms; breaking time: 50 ms; closing time: 6440 ms; average ambient temperature: -30 oC up to +40 oC; design altitude: 1,000 m.a.s.l. GL 308 F1/3120 and GL 308 F3/3120 (52 kV, 60 Hz) — rated frequency: 60 Hz; rated normal current: up to 2,000 A; rated short-circuit breaking current: up to 25 kA; rated short-circuit making current: 65 kA; rated duration of short-circuit: 3 s; opening time: 38 ms; breaking time: 50 ms; closing time: 6440 ms; average ambient temperature: -30 oC up to +40 oC; design altitude: 1,000 m.a.s.l. GL 309 F1/3120 and GL 309 F3/3120 (72.5 kV, 50 Hz) — rated voltage: 72.5 kV; rated frequency: 50 Hz; rated normal current: up to 2,000 A; rated short-circuit breaking current: up to 31.5 kA; rated short-circuit making current: 80 kA; rated duration of short-circuit: 3 s; opening time: 38 ms; breaking time: 50 ms; closing time: 6440 ms; average ambient temperature: -30 oC up to +40 oC; design altitude: 1,000 m.a.s.l. GL 309 F1/3120 and GL 309 F3/3120 (72.5 kV, 60 Hz) — rated voltage: 72.5 kV; rated frequency: 60 Hz; rated normal current: up to 2,000 A. These live tank circuit breakers are intended for outdoor installation as 52 kV (GL 308) and 72.5 kV (GL 309) switching/protection devices. The design and third-generation self-blast interrupter chambers are presented as providing a high level of reliability under extreme conditions, varied climates and in highly active seismic areas. The breakers are supplied preset, pre-filled with SF₆ and completely pre-assembled to allow quick and easy installation on site and to enable long intervals between maintenance. Available configurations include three-pole operated breakers with pole columns mounted on a base frame and single-pole operated breakers with a base frame that has mounted and wired mechanisms, and the interrupter chamber can be disassembled independently of the pole column.